The American Food and Drug Administration (FDA) has approved OCREVUS™ (ocrelizumab) for the treatment of both relapsing and primary progressive forms of multiple sclerosis. This makes ocrelizumab the first ever FDA approved medication for primary progressive MS.
Here in Australia, ocrelizumab has been submitted to the TGA (Therapeutic Good Administration), the Australian equivalent of FDA. We are waiting for their decision to know whether ocrelizumab will be approved for use in Australia, and whether they will follow the FDA and approve it as a first line medication for both relapsing and primary progressive MS. Relapsing MS may also include people with secondary progressive MS if they are still experiencing relapses and/or MRI lesions. A first-line treatment means that people with MS don’t necessarily have to try other MS therapies before taking it.
Ocrelizumab is a type of medication known as a monoclonal antibody. It targets a specific type of immune cell, called B cells, and it lowers the number of B cells circulating around the body. These cells normally help the body fight off foreign invaders protecting against infections and producing antibodies, but in MS they are believed to be misguided and contribute to the immune-mediated attack on the central nervous system.
Ocrelizumab is administered as an intravenous infusion every six months. The first dose is given as two infusions, two weeks apart. Subsequently doses are given as a single infusion.
It is important to note ocrelizumab may not benefit all people with primary progressive MS and is unlikely to completely halt progression. However, clinical trials in 732 people with primary progressive MS, comparing ocrelizumab to a placebo (dummy) infusion, showed that ocrelizumab significantly reduced the risk of disability progression by 24% compared to the placebo. It also decreased the volume of brain lesions.
In trials of 1656 people with relapsing-remitting MS, ocrelizumab significantly reduced the relapse rate by up to 47% and significantly delayed disability progression by 40% compared to interferon beta-1a (Rebif) as well as reducing the inflammation as seen on MRIs. For more detail on the trial results see our earlier article here.
Like any medication, there are potential side effects including, infusion-related reactions, increased risk of infection, and the clinical trials indicate a slight increase in the risk of developing cancers.
We will need to await the review from the TGA and Pharmaceutical Benefits Advisory Committee before we know when Ocrevus may become available in Australia and for whom it will be recommended.
MS is a very varied disease, and not all medications will work for all people. However, the addition of another weapon in the arsenal is very promising and the fact this is the first medication for primary progressive MS is exciting.